Plaster board machine



June 7, 1932. G. H. A. RUBY 1,862,313

PLASTER BOARD MACHINE Filed Jan. 6, 1930 3 Sheets-Sheet l M m g UAM y WN MW m .W WV

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.III 'III PLASTER BOARD MACHINE Filed Jan. 6, 1930 3 Sheets-Shea?l 2 Us \e June 7, Q H. A RUBY PLASTER BOARD MACHINE Filed Jan. 6, 1930 3 Sheets-Sheet 3 Patented June 7, 1932 UNITED STATES GEORGE n. A. RUBY, or LINDEN, Nnw ."IERSEYY v BLASTER BOARD MACHINE Applicationkled January 6, 1930. Serial No.`418,793.

This invention relates to a process of making plaster board and a machine for performing and carrying out the process. Plaster board, as it is known, is ordinarily made from a cementitious mixture which in its hardened and set form has a certain degree of strength but ordinarily to save the board, which is seldom over 1%; to 1/2 of an inch in thickness fromv breaking, it is covered on bothsides and sometimes at its side edges with a paper covering.

In my invention it is contemplated that the cementitious material from which the main body of the plaster, board is made shall be thoroughly intermixed with a vegetable nonstaining fiber, one example of'which is cot-- ton linters or other cotton fiber, the main-portion of the fibrous material being at the center of the board and c ementitious material being` at the opposite sides, though thefibrous material in greater or less degree extends into and binds with they cementitious material substantially to the surfaces of the opposed sides 'of the board. And in the plaster board which I am to make there will be no covering of paper orequivalent material, inasmuch as the board withy the interposed and intermixed fibers is strengthenedV and `reinforced and toughened so that it will not break readily nor will it chip and crack when nails or other like fastening materials are driven therethrough. j l

It is anobject and purpose ofthe present invention to provide a novel process andmachine for manufacturing the plaster board wherein it-can be made continuously and cut into the vari/ous lengths desired for practical applying `of the same to the walls and ceilings of a room for finish thereof in place of lath and plaster', for which plaster board is becoming morev and more used as a substitute. An understanding of the machine construction'and of the process which. is performed thereby may be had from the following description, taken in connection with the accompanying drawings, in which,

Figs. 1 and 2 are, respectively, longitudinal vertical sections throughthe front and the rear end portions of the machine.

Figs. 3 and 4 are, respectively, plan views of the front and the rear end portions of the machine. v A .Fig 5` is a transverse vertical section substantially on the plane of line 5--5 of Fig.v 4, and

Fig. 6 is a perspective view of alength of plaster board-made in accordance with m process.

Like reference characters refer tolike parts l in the different figures of the drawings.

In the construct-ion of the machinesJ plurality of end `and side posts-1 are provided in spaced apart relation to each other between which elongated horizontal rails 2, one set near the upper side andthe other near the lower side of the machine are secured making an elongated frame on which the mechanism of the machine is supported.` Adjacent each end and at each side ofthe machine suitable bearings 3 arev provided for horizontalshafts 4 on whichr drums 5 are mounted for carrying an endless belt 6 which is disposed the full length `of the machine.' The belt is of a suity i cent small rollers7 and the lower run of 'theA belt by other rollers v8 spaced farther apart than the rollers 7'. The ends of the rollers are reduced in size or mounted on suitable shafts and rotatably supported in bearings 9 carried on the horizontal side frame members 2 of the machine.

The rear shaft 4 is driven by an electric motor 10 through interposed reduction gearing 11, as shown in Fig. 4, whereby the upper run of the belt may be continuously movedk at a slow speed from .the front toward the rear of the machine.

At the rear end portion of the machine and above the belt 6 a second endless belt is mounted. Spacedl apart rollers 12 are mounted on horizontal shafts which at their ends have rotatable mounting in bearings 13 secured t0 and adjacent the upper ends of the rear end posts 1 and certain of the side posts 1 located a distance in front ofthe rear end of the machine. Around these rollers or drums 12 an endless belt 14 is mounted being of sufficient width to lap over and lie against the upper sides of the flanges 6a of the belt 6 at its upper run. The belt 14 is also of suitable rubber material and its lower run passes under a pluralit of closely adjacent transverse rollers 15, similar to the rollers 7, having reduced ends on their shafts at their ends mounted in bearings 16, similar to the bearings 9, which are carried by horizontal angle bars 17 located above and parallel to the upper bars 2 at the rear end portion of the machine. The shaft of the rear roller 12 is desi ed to be driven from any suitable source o power to drive the belt 14 in synchronism with the longitudinal movement of the belt 6. The power for driving said shaft is not illustrated as it is obvious that the belt can be driven readily and from the motor 10 is desired. l

Closely adjacent to the front end of the machine a hopper 18 is located above the upper run of the belt 6 on the front posts 1 of the machine and has an opening at its lower end with a gate 19 for gauging the width of the said opening. A feed roller 20 is mounted between the upper ends of the front posts 1 at the lower side of the hopper and on driving the same in the direction indicated by the arrow in Fig. 1 cementitious material from the hopper may be fed on to the belt.

A short distance back of the hopper 18 a bin 21 for holding the fibrous material 22, preferably cotton linters, is located and it is supportedy by suitable supports such as certain of the posts 1 and other posts attached to and extending upwardly from the uppervbars 2 of the frame. At the lower open end of the bin 21 two rollers 23 are mounted in spaced apart relation around which is an endless feed belt 24 having projecting picker fingers 25 directly against which the fibrous material comes so that it may be carried from the hopper and feed on to the belt 6 above the layer of cementitious material which has first been fed thereto from the hopper 18. The roller l20 and the rear roller 23 may be driven by any suitable power source.

Back of the hopper 21 is a water tank 26 supported above the belt and having outlet pipes 27 at its lower side connected with a horizontal pipe 28 perforated at its lower side at a number of points for sprinkling water upon the layer of brous material throughout its width as it passes.

A roller 29 corrugated with a plurality of continuous grooves 30 around it is mounted for rotation back of the tank 26 and in a position to engage against the cotton linter fibrous material as it passes underneath the rollers, thereby working the fibrous material into the lower cementitious material and a second hopper 31, similar in all respects to the hopper 18, is mounted in the same way, having a controlling gate 32 anda feed roller 33 to deliver a second layer of cementitious material to and above the fibrous material as it is carried thereunder by the belt 6.

The process which is performed by the machine is that of depositing the first cementitious layer or strata 34 directly against the upper side of the upper run of the belt 6 between the flanges 6a. The fibrous layer 35 in a uffy separated state is then delivered from the hopper 21 directly over the first layer 34 of the cementitious material, which preferably consists mainly of plaster of Paris with the usual accelerator for quick setting the same and with a small percentage of Portland cement mixed therewith if desired. The water from the pipe 28 is sprinkled continuouslyI by the jets 36 on to the fibrous strata 35 as it passes, sufficient water being provided to supply the necessary water of crystallization for the cementitious material and the first layer of which lies below the fibrous strata and the last one above. When the first strata of cementitious material with the strata of fibrous material above it passes from the sprinkler it comes to the corrugated roller 29Vwhich compresses the fibrous material forcing the water downwardly through it to the lower layer 34 of the cementitious material and working the fibrous material and the cementitious material together. The final deposit of material is the upper layer 37 of cementitious material from thehopper 32 directly back of which is the front end of the belt 14 whose lower run is located directly against the upper sides of the flanges 6a of the belt.

When the composite material in the layers or strata described passes underneath the lower end of the belt 14 there is a heavy compression of the fibrous material which forces thefwater into the cementitious material both above and below. Sufficient water is provided to supply all that is needed to crystallize and set the cement. The length of the belt 14 is such that by the time the board passes from underneath the belt 14 the cementitious material has crystallized and set and has been forced into intimate and intermixed relation with the fibrous material the cement from the upper end of the lower mixers or strata 34 and 37 permeating through to completely cover or dust the fibers so that when the pressure occurs as it passes underneath the belt 14 the cement adhering to the fibers crystallizes and sets and the board 38 passing from the belt 14 is a set and hardened cementitious mixture throughout Which there is interspersed the fibrous material of the intermediate layer 35 all securely joined and bound together by the crystallizing and setting of the cementitious material; and the board as it passes from the machine may be sawed into any desired lenfrth, as indicated at 89 in Fig. 6, use being ma e of the usual and conventional plaster board cut-olf saw.

The machine and process described are particularly useful for producin laster board of the character outlined W ic does not require any paper covering for strength and reinforcement and to keep the same from breaking or cracking during handling or when nails or brads are driven therethrou h. The invention is defined in the appen ed claims and is to be considered comprehensive of all forms of structure coming within their scope.

l claim:

l. Mechanism of the class described comprising an endless horizontal conveyor means for driving the conveyor, means for continuously depositing dry cementitious material on to the moving conveyor, means for continuously depositing picked apart fibrous material in fluffy condition on to said layer of cementitious material, means for sprinkling Water on the iibrous material as it moves with the conveyor, means for continuously depositing a second upper deposit of dry cementitious material on to said fibrous material, and compression means under which said layers of materials are carried by said conveyor located above the conveyor and serving to compress said layers of material together and permeate said cementitious materials With Water, combined with means on said conveyor at its sides to hold said materials from side movement.

2. In a machine of the class described, an endless, horizontal conveyor having spaced apart upwardly extending anges at its sides thereby providing a continuous relatively Wide and shallow trough at the upper side of Jthe conveyor, means for driving the conveyor, means for continuously depositing a substantially uniform layer of dry cementitious material in said trough on the conveyor as the same is moved, means for cont-innously depositing picked apart fibrous material in iuii'y state on and above said cementitious material as t-he conveyor is moved, means for continuously sprinkling Water against the upper side of said fibrous material Vas itvmoves With the conveyor, a grooved roll er underneath which said first cementitious material and sprinkled fibrous material passes. means for continuously depositing a second substantially uniform layer of dry cementitious material on and above the fibrous material and an endless horizontal belt located above and parallel to the upper side of the conveyor underneath which said layers of material are carried for a distance said belt bearing against the upper sides of said anges to thereby compress said cementitious and fibrous materials together within the trough of the conveyor and hold them compressed until said cementitious materials have hardened and set.

In testimony whereof I aix my si ature.

GEORGE H. A. RlBY. 

